Datasheet

Section 12 Serial Communication Interface
Rev.7.00 Dec. 24, 2008 Page 390 of 698
REJ09B0074-0700
1234 567891011121314 15 16 17 18 19 20 21 2322 24 25 1 2 5 6 7 8 9 1011121314 15 16 17 18 19 20 21 22 23 24 253 4
12 MHz
5.76 MHz
123
3 MHz
1.8421 MHz
4 567891011121314 15 16 17
1
18 19 20 21 2322 24 25 26
23 4 56789101112 1413 15 16
27 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 495051525354 55 56 57 1 228
29
123
12 MHz
7.3684 MHz
4 567891011121314 15 16 17
1
18 19 20 21 2322 24 25 26
23 4 56789101112 1413 15 16
27 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 495051525354 55 56 57 1 228
29
123
12 MHz
7.3684 MHz
4 567891011121314 15 16 17
1
18 19 20 21 2322 24 25 26
23 4 5678
1
234 5678
27 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 495051525354 55 56 57 1 228
29
Base clock
24 MHz/2 = 12 MHz
12 MHz × (12/25)
= 5.76 MHz
(Average)
Base clock with 720-kbps average transfer rate (ACS3 to ACS0 = B'1010)
Average transfer rate = 5.76 MHz/8= 720 kbps
Average error with 720 kbps = ±
0%
Base clock
24 MHz/2 = 12 MHz
12 MHz × (35/57)
= 7.3684 MHz
(Average)
Base clock with 921.053-kbps average transfer rate (ACS3 to ACS0 = B'1011)
Average transfer rate = 7.3684 MHz/8= 921.053 kbps
Average error with 921
.1 kbps = -0.059%
Note: * The lengh of one bit varies according to the base clock synchronization.
Base clock
24 MHz/2 = 12 MHz
12 MHz × (35/57)
= 7.3684 MHz
(Average)
1 bit = base clock ×
16*
1 bit = base clock × 8*
1 bit = base clock × 8*
Base clock with 460.526-kbps average transfer rate (ACS3 to ACS0 = B'1001)
Average transfer rate = 7.3684 MHz/16 = 460.526 kbps Average error with 460.6kbps = -0
.059%
1 bit = base clock × 16*
Base clock
24 MHz/8 = 3 MHz
3 MHz × (35/57)
= 1.8421 MHz
(Average)
When φ = 24 MHz Base clock with 115.132-kbps average transfer rate (ACS3 to ACS0 = B'1000)
Average transfer
rate =1.8421 MHz/16 = 115.132 kbps
Average error with 115.2 kbps = -0.0059%
Figure 12.3 Examples of Base Clock when Average Transfer Rate Is Selected (3)